Combined fuse and disconnecting device



March 27, 1956 D. o. HAGGLUND ETAL 2,740,014

COMBINED FUSE AND DISCONNECTING DEVICE 2 Sheets-Sheet 1 Filed Sept. 16, 1952 .l IIIIIIIL March 27, 1956 O HAGGLUND ET AL 2,740,014

COMBINED FUSE AND DISCONNECTING DEVICE 2 Sheets-Sheet 2 Filed Sept. 16, 1952 Ill.ITllTilllllllrlllllllllll 25 25 1o 27 I8 20 a2 75 United States Patent 2,740,014 COMBINED FUSE AND DISCONNECTING DEVICE David Olof, Hiigglund, Omskoldsvik, and Aine Evert Erling Jansson, Sundsvall, Sweden Application September 16, 1952, Serial No. 309,904 claims priority, application Sweden September 20, 1.951 2 Glaiins. (Cl. 200-114 Our present invention relates generally to electrical fuses and" more particularly with a device for removably mounting fuses in a protective housing having safety means for insuring their safe disconnection and removal.

Our invention is mainly characterized by a fuse carrier mechanism" having a contact fork adapted to grasp the lower contact tongue of a cartridge style of fuse and a guiding member having an opening therein for receiving the opposite tongue of the fuse cartridge. A disconnector clamp is also arranged for arcuate movement adjacent one end of the fuse and carries therewith a second contact fork capable of making circuit closing connection with the upper contact tongue of the cartridge fuse.

The main object of our present invention is to provide a new and improved means for carrying cartridge type fuses.

Another object of our invention is to provide a new and improved fuse carrier having means for mounting a cartridge style fuse in a stationary position irrespective of the fuse disconnector device associated therewith. Still'anotlier object of our invention is to provide a fuse disconnect means for use with the fuse carrier of our invention wherein only two contact surfaces present a transition resistance during the making and breaking of circuits through the fuse;

A still further object of our invention is to provide a new and improved fuse carrier and disconnect means in which means are embodied to provide safe and expeditious replacement of burned out fuses to promote safety of operating personnel.

Still another objector our present invention is to pro vide anew and improved combined fuse carrier and disconnect device combining elements arranged in a compact and unified manner and capable of economical manufacture; I

The above and further objects and characteristic features of our present invention will be obvious to one familiar with the'art from the following description thereof and with reference to the accompanying drawings.

In the drawings:

Figure l is a side elevational view, in partial crosssection', of the combined fuse carrier and disconnecting device according to our present invention;

Figure 2 is a top plan view in partial section of the device shown in Figure l; and

Figure 3 is'a front elevational view, in partial section, of the new and improved fuse carrier and disconnecting device'of' our invention.

Withreference to Figure 1 of the" drawings, itwilllie recognized that we utilize a base plate member 1 having backwardly bent side flange portions 2 for supportiiig three sockets 4" made of steatite or some other suitable dielectrical material which are fastened on the base plate 1 by bolt means 3. Each of the sockets 4 is provided at its lower end with an electrically conductive contact fork member 5. The lower end of each contact fork 5 is suitably provided with a connection screw 6 to which conductor wire (not shown) is to be fastened. Each socket 4 is further provided adjacent its upper end with an L-shaped" bracket 7, one arm 8 of which is connected to its associated dielectric socket 4. A second, trans versely extending arm 9 of each bracket 7 is provided with a central slotted opening 10 formed inwardly from the leading edge of the bracket arm 9. Each slot 10 is formed in such a manner and each bracket 7 is placed at such a position and distance from its related contact fork 5 that a conventional fuse cartridge 11 may be placed; in operative position therebetween so that a lower conta'ct tongue 12 of the cartridge will be squeezed or embraced by the contact fork 5 and an upper contact tongue 13' of the'cartridge will be guided and embraced in slot 10, substantially as illustrated in Figure 3 of the drawings Disposed transversely between and projecting through the flange portions 2 of the base plate 1, adjacent the upper end thereof, is a shaft member 14. The free ends of shaft 14 are connected with a U-sha'ped discon'rictor clamp 15 made of dielectric material mounted outwardly of the flange portions 2, substantially as shown in Figure 2 of the drawings. Clamp 15 is adapted to swivel with shaft 14 by means of an op rating handle or the like (not shown), but associated with an arm member 16 and a link 17, the latter of which is rigidly connected to the bracket member 15 at its right hand end, as illustrated in Figure 3 of the drawings. The clamp 15 further omprises apair of parallel bars 13 formulated at its front end or forming the base portion of its U configuration. The bars 18 support three contact forks 20, of electrically conductive material, which are fastened to the arms 18 by bolt means 19 and depend in parallel spaced position beneath arms 18, substantially as shown in Figure 3 of the drawings.

It will further be noted that the several contact forks 20 are located in the same vertical plane and are spaced according to the lateral spacing of the cooperating stationary fork members 5 and bracket slots 10 described heretofore. The arms of forks 20am further aligned to receive the upper contact tongues 13 of the cartridge fuses therebetween and thus are vertically aligned with slots Illof the brackets'7.

A protective casing or covering for the carrier, having dimensions in keeping with the base plate 1, is mounted outwardly ofthebracke t member IS and connected there to by means of bolts or screws 21, substantially as illustrated. For sake of convenience, it is preferred that the protective case 22 be made of a transparent dielectric materia so that the operation of the fuses maybe ob servedwithoiitremoval of the cover or casing. The protctive' case further comprises a front wall 23, two side walls'24, 24 and located for passage intermediate the middle and end disposed socket members 4 of the carrier assembly. The purpose of the casing, of course, is'to enclose the current carrying parts of the device illustrated and such is adapted for fringing or arcuate 15'as shown by'the phantom lines of Figure 1.

Operation With cartridge style fuses 11 positioned as shown in Figure 3 of the drawings, so that the lower tongues 12 thereof are grasped or clamped by the lower stationary fork members 5 and the upper tongue members 13 thereof are located'inthe' slotted apertures 10 of brackets 7,

disconnection of the circuit through the fuses is accom-,

a pair of spark guard partitions" 25 movement with the clamp member 22 and the disconnect bracket 15 and are thus swung upwardly away from the fuses to break circuit connection therewith. The fork members 20 of course are the hot forks of the switching system and are provided with current by means of conductor wires 26, or the like, as shown in Figure 1. Since the cover member or casing 22 interferes with the extension of the operators hand to engage the fork members 20 and also safely separates the lower fork members from the fork members 20, by carrying the latter with it to its upwardly swung position, the device of our invention thus provides a safety factor giving it distinct advantage over prior art devices of this character. The exchange of fuse cartridges ll for new ones may be carried on without risk to the operating personnel since at the breaking of circuit therethrough by swinging the hot fork members 20 to their upward or off switch position, the lower fork members are thereby deenergized or disconnected from the circuit and are thus dead. The insulated relation of the guiding bracket 7 further enhances the dead condition of the cartridge fuse members 11. When the cover member and upper fork members are swung downwardly to place the device into circuit again, the contact forks swing with the cover to embrace the upper tongues 13 of the cartridge fuses and push the same tightly against the rear ward side of the slotted apertures 10 formed in bracket arms 9. Thus the fuse cartridges are steadily positioned in operative condition in the fuse carrier and good contact is obtained between the upper contact tongues 13 and the hot" upper contact forks 20.

The novel advantage of constructing the casing 22 of a transparent dielectric material will be appreciated especially since it gives the operator a visual observation of the position of the fork contact members 20 during the changing of a burned-out fuse. Further, it will be appreciated that the front wall portion 23 of the casing or cover 22 provides a shield to prevent the introduction of the operators hand to the hot contact members 20 and thus prevents him from completing circuit across the upper and lower contact forks 20 and 5, respectively, through the intermediary of his hand. Such a safety feature marks our instant invention as an advantageous advancement over prior art devices and gives rise to a new and improved fuse carrier and a disconnect means as described hereinabove.

The embodiment shown and described herein is to be considered only as one example of how the features of our present invention may be embodied in a workable device and it will be understood that various parts of the combined fuse carrier and disconnecting device may be embodied in other ways and manners within the scope of our invention. For example, it may be convenient to have the upper contact forks 20 movable vertically or at an incline relative to the upper contact tongues 13 of the fuse cartridges 11. Such a change may be carried out in accordance with known concepts without departing from the spirit and scope of our invention and therefore this change is contemplated as one modified form of our present invention which may be carried out with marked advantage in certain situations and conditions. Likewise, in order to prevent the dislodging of the fuses during disconnecting movement of the contact forks 20 from the tongue portions 13 of the cartridge fuses 11, it may be desired to embody a different style of aperture in the platform portion 9 of bracket members 7 and to that end it is contemplated that the aperture 10 may be enclosed at its forward end, suchas is indicated by dotted lines in Figure 2 of the drawings. Other arrangements and modifications of the features of our present invention will be suggested to one familiar with this art, but it is fully intended that such obvious modifications will come within the realm of our present teachings.

Further the concepts and teaching of our present invention may be applied to one, two or multiple disconnector units as desired and spring means or the like may be utilized with the cover to accommodate a quick break in the disconnect of the fork members 20 and the tongue portions 13 of the cartridge fuses 11. In any event, while various changes, modifications and substitutions of equivalents may be made in our present invention, it is our intention that such will not depart from the spirit and scope of our invention. Therefore, we do not wish to be limited to the specific embodiment of our invention herein illustrated and described exceptas may appear in the following appended claims.

We claim:

1. A combined fuse carrier and disconnecting device of the class described for use with a cartridge style of fuse, comprising, a first electrically conductive contact fork mounted on an insulating base plate for engaging one contact tongue of a cartridge fuse, a guiding member disposed on the base plate in spaced relation from said first contact fork, said guiding member having an open ing aligned with said fork for the inserted reception of a second contact tongue of a cartridge fuse, a disconnector means pivotally secured adjacent the upper end of said base plate for arcuate movement toward and away from said guiding member, a second electrically conductive contact fork mounted on said disconnector means and engageable with the second contact tongue of said fuse when said disconnector means is moved to its lowermost arcuate position, and a casing of transparent dielectric material carried on the outside of said disconnector means and enclosing the second contact fork, said casing being arcuately movable with said disconnector means and positioned thereon to cover said second named contact fork in the said lowermost position of said disconnector means.

2. A combined fuse carrier and disconnecting device of the class described for use with a cartridge style of fuse, comprising, a first stationary electrically conductive contact fork mounted on an insulating'base plate for engaging one contact tongue of a cartridge type fuse, a guiding member disposed on said base plate in spaced relation with said first contact fork, said guiding member having a slotted opening aligned with said first fork for the inserted reception therein of a second contact tongue of said cartridge fuse, said guiding member embracing said second contact tongue substantially at its base end thereby to permit a free end portion of said second contact tongue to protrude beyond said guiding member when the same is in its inserted position therein, a disconnector means pivotally secured adjacent the upper end of said base plate for movement toward and away from said guiding member, and a second electrically conductive contact fork mounted on said disconnector means for engaging the said protruding free end portion of the second contact tongue beyond said guiding member when said disconnector means is moved to its operative position.

References Cited in the file of this patent UNITED STATES PATENTS 

